On Wed, Nov 23, 2022 at 6:46 PM Vojtech Trefny vtrefny@redhat.com wrote:
Hi, I am planning to change how we support BIOS RAID (sometimes also called Firmware or Fake RAID) in the installer in the future. I plan to go through the official Fedora change process for Fedora 38, but I'd like to get some feedback first.
We are currently using dmraid to support these types of RAIDs in blivet[1] (storage library the Anaconda installer uses) and we would like to replace it with mdadm. The main reason is that dmraid is no longer actively maintained, but it will also mean one less dependency for the installer (we use mdadm for the software RAID support) and one less service running during boot (dmraid-activation.service).
The potential issue here is that mdadm doesn't support all BIOS RAID types. mdadm supports only Common RAID Disk Data Format standard[2] (DDF) and Intel Matrix Storage Technology (IMSM) so by switching to mdadm we would remove support for some of the older formats that existed before DDF was standardized. I am not sure how many people are still using these older RAIDs and the main reason for sending this email is to find out. So if you are using a BIOS RAID on your system, can you check what kind? You can find out simply by checking the filesystem type on the underlying disk(s) reported by for example `lsblk -f`. Types supported by mdadm are "ddf_raid_member" and "isw_raid_member".
Hi Vojtech. I just confirmed that our Fedora QA test machine in Brno has isw_raid_member-type RAID, so I'm happy to report that we can continue testing Firmware RAID even after this change ;-)
Kamil